Following a (terrorist, accident, or during radiation therapy for cancer) radiation exposure either to the whole body or localized to a region of the body, tissue/organ injury results in part because of a loss of stem cells.
Peripheral blood stem cell mobilization, which has become extremely important as a source of hematopoietic stem cells for bone marrow transplantation over the last 15 years, is generally performed using the cytokine drug, G-CSF, but is ineffective in around 15 to 20% of patients. Other agents have been used to mobilize and enhance G-CSF-induced mobilization. The stem cell factor was investigated, but was withdrawn from clinical development due to its toxicity.
There is a need to develop pharmacologic agents that can reduce late tissue injury including skin in the time after a radiation exposure.